Web processing device

ABSTRACT

A photographic processing device or the like in which a web being transported is engageable at one or more stations by processing rollers having a nonsmooth or roughened periphery, and whose peripheral speed exceeds the transport speed of the web. The processing device includes mechanism for driving the rollers in one direction so that the portion of the periphery thereof engageable with the leading end of the web is moving in the direction of web transport, and for reversing the direction of rotation of the rollers so that the portion of the periphery thereof engageable with the trailing end of the web is moving in the opposite direction of web transport.

United States Patent [72] lnventor William L. Cuthbert Rochester, N.Y.[21] AppL-No. 756,676 [22] Filed Aug. 30, 1968 [45] Patented Jan. 5,1971[73] Assignee Eastman Kodak Company Rochester, N.Y.

a corporation of New Jersey [54] WEB PROCESSING DEVICE 9 Claims, 2Drawing Figs.

[52] [1.8. CI 95/94, 95/89 [5l] Int. Cl 603d 3/12 [50] Field of Search95/94, 89

[56] References Cited UNITED STATES PATENTS 1,825,728 l0/l93l Hall 95/941,924,994 8/1933 Knapp, Jr. 95/94UX 2,460,282 2/1949 Gardner 95/89UX3,134,314 5/1964 Greenwold 95/94X Primary Examiner-John M. HoranAssistant Examiner-Richard L. Moses Att0rneys Robert W. Hampton andSteve W. Gremban 'mechanism for driving the rollers in one direction sothat the portion of the periphery thereof engageable with the leadingend of the web is moving in the direction of web transport, and forreversing the direction of rotation of the rollers so that the portionof the periphery thereof engageable with the trailing end of the web ismoving in the opposite direction of web transport.

PATENTEU JAN 519m mm Iotim WILLIAM L. CUTHBERT on IPEEW KNEE.

INVENTOR. BY M ATTRONE YS WEB PROCESSING DEVICE BACKGROUND OF THEINVENTION This invention relates generally to processing machines, andmore specifically to an improved web processing device or the like.

In processing metal plates to be used as masters in a printingoperation, it is desirable to scrub a sensitized sheet to removedissolved polymer therefrom. This exposes the undersurface of the plateto the developing solution and enhances the development action. For thispurpose, rollers having a roughened or nonsmooth scrub surface have beenused with the scrub surface moving at a speed faster than the transportspeed of the plate. However, such differential movement has a tendencyto damage the leading or trailing end of the plate in those situationswhere the scrub surface is moving in a direction opposite to the platemovement. This problem has been solved by providing an improvedprocessing device in which the direction of rotation of the processingrollers is automatically altered in relation to the leading and trailingends of a sheet so that the ends thereof are not damaged as the sheetsare transported through the processing rollers.

SUMMARY OF THE INVENTION This invention includes within its scope animproved web processing device in which the peripheral speed ofnonsmooth processing rollers exceeds the transport speed of a web suchas sheet or the like, and the direction of rotation of the processingrollers is periodically altered in relation to the leading and trailingends of the sheet to prevent damage thereto.

One of the objects of the present invention is to provide a processingdevice for a web in which the direction of rotation of the processingrollers is controlled in relation to the leading and trailing ends ofthe web so that no damage results thereto.

Another object of the invention is to process webs with rollers havingrelative motion between the web and roller surface in engagementtherewith without damaging the trailing or leading ends of the web.

Objects and advantages other than those set forth above will be apparentfrom the following description when read in con- I nection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a schematic view in side elevation of a processing device inwhich a preferred embodiment ofthis invention is incorporated; and

FIG. 2 is an electrical circuit diagram for the processing device ofFIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, thisinvention is shown in connection with a film processing device 4 havingin succession a solution applicating station 6, a sheet detectingstation 8, a developing station 10, a desensitizing station 12, and adrying station 14. A processing device of this type is particularlyuseful for the processing of metal plates for use as masters in aprinting operation. The processing device 4 has'a transport mechanismfor transporting a web such as a sheet of photographic material or thelike which is to be processed through the aforementioned stations of theprocessing device. The transport mechanism comprises a plurality ofopposed, engaged pairs of transport rollers 16, 16' spaced such that thedistance between the pairs of transport rollers l6, 16' are less thanthe length of a sheet. Accordingly, at least one pair of transportrollers is in engagement with a sheet 15 or plate at all times. A sheet15 of photographic material introduced into the nip of the entrancetransport rollers 16' is transported through the solution applicatingstation 6 where a developing solution 17 is applied to the sheet by anywell known solution applying devices such as spray heads shownschematically at 18. The

solution is spread evenly on the sheet by a resilient flap 20V pivotallysecured to a rod 22 at one end and having its free end urged by gravityinto engagement with the sheet. Any excess solution 17 from sheet 15drops into an inclined catch pan 24, and is returned by gravity into adeveloper tank 26 at the developing station 10. The catch pan 24 isshown integral with tank 26, although it may be separately fabricatedand secured to pan 24 by any suitable means. Two pairs of theaforementioned transport rollers 16 are positioned at the developingstation 10 with the lower rollers thereof partially immersed in thedeveloping solution 17 for applying solution to the sheets 15 andtransporting the sheets therethrough.

At the desensitizing station 12, pairs of opposed, engaged transportrollers 16 are positioned at the entrance and exit of the densitizingstation, the lower roller of each pair being partially immersed in adesensitizing solution 24. In metal plate processing devices, thedesensitizing solution may be a gum solution for applying gum arabic tothe processed plate to protect it.

The drying station 14 may comprise any suitable dryer, in this instanceshown as a pair of opposed plenums 26 having nozzles 28 thereinfordirecting heated air into engagement with opposite surfaces of theprocessed sheet 15 for guiding the sheet through the drying station andinto the nip of a pair of transport rollers 16. The dried sheet 15 isguided around a curved path by a plurality of idler rollers 30 and intothe nip of a pair of exit rollers 16 which transport the sheet throughan exit opening 32 in the device 4 and onto the top 34 of the device.

A first pair of opposed, engaged processing rollers 36 is positioned atthe entrance of the developing station 10 with the lower rollerpartially immersed in the developing solution 17 for applying solutionto the nipof the rollers. In this application, theprocessing rollers 36have a roughened periphery for scrubbing the sensitized sheet 15 toremove dissolved polymer in the case of metal plates, to increaseagitation, and to flood the sheet with solution. Two other similar pairsof opposed, nonsmooth processing rollers 36 are interposed between theaforementioned pair of transport rollers 16 at the developing station 10with the'lower rollers thereof also partially immersed in the processingsolution 17.

At the desensitizing station 12,-a pair of opposed, nonsmooth processingrollers 36 similar'to the aforementioned processing rollers areinterposed between the transport rollers with the lower roller of eachpair partially immersed in the desensitizing solution 24. In the case ofmetal plates, these rollers 36 remove developer from the plate, andapply thereto a gum arabic protective coating.

The transport and processing rollers 16, 36 are driven by separate drivemotors 40, 42 respectively of any suitable type under the control of atimer mechanism of known type. The entrance transport rollers 16 intowhich the sheet is first introduced are connected to the transport drivemotor 40 through a clutch 44. The operation of the transport andprocessing rollers 16, 36 in relation to a sheet 15 being transportedthrough the processor 4 is controlled by a control system shown in FIG.2 which includes any suitable sheet detector switch 46 shown in FIG. 2as a single pole, double throw switch, and having an arm 46' positionedbetween the entrance transport rollers 16' and the first pair ofprocessing rollers 36 and engageable by the leading end of a sheet 15for a purpose to be explained hereinafter.

The operation of the photographic processing device 4 will now bedescribed in relation to FIGS. 1 and 2 of the drawings. Initially,turning on the processing device by closing any suitable on-off switch,not shown, connects the power supply to the transport and processingmotors 40, 42 respectively for driving the transport and processingrollers. A sheet 15 of exposed photographic material is initiallyintroduced into the processing device 4 through an inlet opening 48, andfed into the nip of the entrance transport rollers 16' which are drivenin a direction shown by the arrow to transport the sheet through theprocessing device. The sheet 15 is transported through the sprayingapparatus 18 which directs developing 'soltition on both sides of thesheet. The leading edge of sheet 15 moves detector arm 46' and switch 46from its normal position A to a' position B. This electrically connectsthe power source through a normal position C of a single-pole,doublethrow timer switch 50 to a timer mechanism including a timer motor52 and a cam system 54 driven thereby to initiate operation of the timermotor 52. The sheet 15 is transported by transport rollers 16 betweenthe processing rollers 36 at the developing station subjecting the sheetto the action of the processing'rollers 36 which are operating at aspeed in excess of the transport speed of the sheet. As soon assufficient time has elapsed to permit sheet to enter the first pair oftransport rollers 16 at developing station 10, the'cam system'opens anormally closed clutch switch 56 deenergizing clutch 44 anddisconnecting the transport motor40 from the entrance transport rollers26, allowing them to idle. This prevents the introduction of anothersheet 15 into the processor until the entrance transport rollers 16' arereenergized, Substantially simultaneously, the cam system actuates asingle-pole, singlethrow reversing switch 58 moving it from its normallyopen position to its closed position actuating a relay 60. The relay 60moves a single-pole, double-throw switch 62 from its normal position Eto a position F turning off a feed lamp and turning ona no feed lamp.The relay 60 further actuates two single-pole, double-throw switches 64,66 moving switch .64 from normal position G to position H, and the otherswitch I 66' from normal position 1 to position J for reversing thepower leads to the processing roller drive motor 42 for driving all ofthe processing rollers 36 in a reverse direction. Accordingly,

as the trailing end of sheet 15 passes between the pairs 16 of 3processing rollers at the developing station 10, the periphery of theprocessing rollers 36 in engagement with the sheet will be'moving in adirection opposite to the direction of movemerit of the sheet so thatthe roughened surface of the' processing rollers 36, will not damage thetrailing end of the sheet as it passes therethroughl Also, as theleading end of sheet 15 arrives at the nip of the first pair ofprocessing rollers 36 at the desensitizing station 12, the portion ofthe periphery of the processing rollers 36 engageable with the sheetswill now be moving in the same direction as the'sheet, and'hence willnot damage the leading end of the sheet as itenters the nip of therollers. Following reversal of the processing roller drive" motor 42,the cam system moves timer switch to position D deenergizing the timermotor 52;

I When the trailing end of sheet 15 passes the detector switch 46, thedetector switch is returned from position B to its normal position Areactivating the timer mechanism through timer switch 50, now inposition D. When sufficient time has elapsed for the trailing end ofsheet 15 to clear the processing rollers 36 at the developing station10, the cam system returns thereversing switch 58 to its normally openposition deenergizirig relay 60 and returning switches 64, 66 to theirnormal positions E, G respectively to again reverse the direction ofrotation of all of the processing rollers 36 to their normal directionof rotation. Accordingly, as the trailing end of sheet 15 passes betweenthe processing rollers 36 at the desensitizing station 12, the portionof the periphery of the processing" rollers 36 in engagement with thesheet will now be moving in the'opposite direction of the sheet, andhence will not damage the trailingend as it passes therethrough'. Theprocessed sheet 15 enters the drying station 14 where it is subjected toheated air for drying the sheet and guiding the leading end thereof intothe nip of transport rollers 16. The dried sheet 15 is transportedaround the turn-around idler rollers 30, through exit opening 32 andonto the top 34 of the processing device 4.

The invention has been described in detail with particular reference toa preferred embodiment thereof, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention as described hereinabove, and as defined in theappended claims.

lclaim:

l. l'ri{a processing device having a processing station, thecom'bjiiation comprising:

direction of movement of said processing means in timed.

relation to a web transported through said processing device in said onediref ction so that said web engaging portionv when in engagement with.the'leading end of the web is moving in said, no direction of webtransport, and

said web engaging portion when in engagement with the trailing end ofthe web is moving in the opposite direction whereby damage to theleading and trailing ends of the web is prevented as the web istransported through the processing device in said one direction.

2. The invention according to claim 1' wherein said movable processingmeans comprises rollers, having a roughened material engaging surface.

3. The invention according to claim 1 wherein said movable processingmeans comprises a pair of opposed engageable rollers through which theweb is transported, said rollers having a roughened webengaging surface.

4. The invention according to claim 1 wherein said controlling meanscomprises a reversible motor drivingly con nected to said movableprocessing means, a reversing switch for said motor, and means foractuating said reversing switch.

5. The invention according to'claim 4 wherein said actuatstations, andmeans for transporting a web through the stanot in one. direction andinsuccession for processing the ieb, theeornbinationeomprising:

first means atthe firststati'on having a web engaging'portion movable inthe direction of web transport for engaging and processing the web as itis transported therethrough; second means at the second statiori havinga web engaging portion movable in'the opposite direction of web transport for engaging and processing the web as it is transportedtherethrough; and

vmeans coupled 'to said first and second processing means for reversingthe direction of movement of said first and second processingigneans intimed relation during transport of the web whereby when said portions ofsaid first and secondprocessing means engage the leading end of the webthey are, moving in the direction of web transport, and when saidportions of said first and second processing nieans engage the trailingend of the web they are moving v in the opposite direction of webtransport.

7. The invention according to fclaim 6 wherein said reversing meanscomprises a reversible. motor drivingly connected to said first andsecond processing means, a reversing switch for said motor, and meansfor actuating said-reversing switch.

8. The inventiorl according to claim 7 wherein said actuating meanscomprises a cam connected to said switch, and a timer motor for drivingsaid cam;

9. The invention according toclaim 6 wherein said web transporting meanscomprises a transport motor, and transport rollers including-entrancetransport'rollers driven by said transport motor; 'said reversing meanscomprises a reversible motor drivingly connected to said first andsecond processing means, a reversing switch for said reversible motor, acam

1. In a processing device having a processing station, the combinationcomprising: means for transporting a web having leading and trailingends through the processing station in one direction; movable processingmeans at the processing station having a web engaging portion forprocessing the web as it is transported therethrough in said onedirection; and means coupled to said processing means for controllingthe direction of movement of said processing means in timed relation toa web transported through said processing device in said one directionso that said web engaging portion when in engagement with the leadingend of the web is moving in said one direction of web transport, andsaid web engaging portion when in engagement with the trailing end ofthe web is moving in the opposite direction whereby damage to theleading and trailing ends of the web is prevented as the web istransported through the processing device in said one direction.
 2. Theinvention according to claim 1 wherein said movable processing meanscomprises rollers having a roughened material engaging surface.
 3. Theinvention according to claim 1 wherein said movable processing meanscomprises a pair of opposed engageable rollers through which the web istransported, said rollers having a roughened web engaging surface. 4.The invention according to claim 1 wherein said controlling meanscomprises a reversible motor drivingly connected to said movableprocessing means, a reversing switch for said motor, and means foractuating said reversing switch.
 5. The invention according to claim 4wherein said actuating means comprises a cam connected to said switch,and a timer motor for driving said cam.
 6. In a processing device havingfirst and second processing stations, and means for transporting a webthrough the stations in one direction and in succession for processingthe web, the combination comprising: first means at the first stationhaving a web engaging portion movable in the direction of web transportfor engaging and processing the web as it is transported therethrough;second means at the second station having a web engaging portion movablein the opposite direction of web transport for engaging and processingthe web as it is transported therethrough; and means coupled to saidfirst and second processing means for reversing the direction ofmOvement of said first and second processing means in timed relationduring transport of the web whereby when said portions of said first andsecond processing means engage the leading end of the web they aremoving in the direction of web transport, and when said portions of saidfirst and second processing means engage the trailing end of the webthey are moving in the opposite direction of web transport.
 7. Theinvention according to claim 6 wherein said reversing means comprises areversible motor drivingly connected to said first and second processingmeans, a reversing switch for said motor, and means for actuating saidreversing switch.
 8. The invention according to claim 7 wherein saidactuating means comprises a cam connected to said switch, and a timermotor for driving said cam.
 9. The invention according to claim 6wherein said web transporting means comprises a transport motor, andtransport rollers including entrance transport rollers driven by saidtransport motor; said reversing means comprises a reversible motordrivingly connected to said first and second processing means, areversing switch for said reversible motor, a cam connected to saidreversing switch, and a timer motor for driving said cam; saidtransporting means further having a clutch interconnecting said entrancetransport rollers to said transport motor, and a clutch switch for saidclutch actuable by said cam in timed relation to the transport of theweb for disabling said entrance transport rollers to prevent theintroduction of another web into the processing device until saidentrance transport rollers are enabled.